Method of producing synthetic detergent cakes



Nov. 4, 1958 c. F. J. DUPUY 2,853,559

METHOD OF PRODUCING SYNTHETIC DETERGENT CAKES Filed July 1, 1955 INVENTOR.

United States Patent METHOD OF PRODUCING SYNTHETIC DETERGENT CAKES Charles F. J. Dupuy, Allendale, N. J.

Application July 1, 1955, Serial No. 519,357

6 Claims. (Cl. 1847.5)

This application relates to a method for producing syn-' thetic detergent'cakes.

Synthetic detergents, such as the alkyl aryl sulfonates, have long been known as highly eifective cleansing agents, and for many uses have largely replaced soaps. Synthetic detergents, however, have not proven adaptable for use in the form of cakes or bars, and therefore are generally employed as powders. Great pressure is required to form synthetic detergents into cakes which will remain reasonably intact during use. The use of binding agents in combination with the detergent material has been investigated, and some binding agents have been found which were satisfactory where the bars were to be formed by milling and extrusion procedures, involving the application of pressure in the forming of the bars. Small proportions of water-insoluble waxes have been used as binding agents, but all previous attempts to use high proportions of water-insoluble waxes in synthetic detergent cakes have demonstrated its impracticality. The water-insoluble waxes apparently act to suppress the foaming properties of the detergent, which heretofore has been believed to limit their use to less than 10% of the total formulation. On the other hand, water-insoluble waxes have desirable properties such as slush resistance, and have an excellent binding action.

It is therefore a general object of this invention to provide a method of producing synthetic detergent cakes which permits the incorporation of high proportions of water-insoluble waxes without an undue suppression of foam development. Further objects and advantages of this invention in both its method and product aspects will become apparent as the specification proceeds.

The method of this invention is shown in an illustrative diagrammatic flow sheet in the accompanying draw ing, which will subsequently be discussed in detail.

This invention is based partially on the discovery that the undesirable suppression of foam development in synthetic detergent bars by water-insoluble waxes can be overcome to a considerable extent if the bars are formed without the application of any pressure thereto. In fact, the method of this invention permits the formation of satisfactory synthetic detergent bars containing from 30 to 50% or higher percent of a water-insoluble wax.

It is believed that this invention can be best understood by reference to the flow sheet of the accompanying drawing. The process as illustrated there begins at the upper left-hand corner in the jacketed mixing kettle 10. Into this kettle is charged a water-insoluble wax and a synthetic detergent, which together form the principal ingredients of my new product. As shown in the drawing, the kettle 10 is equipped with a stirrer 11 and steam is introduced into the jacket 12 of the kettle for the purpose of heating the mixture of water-insoluble wax and detergent. The combination of the heating and stirring forms a fluid mixture, the temperature being sufficient to melt the wax. Preferably, the water-insoluble wax is used in proportions of from about 50 to 100 parts by weight per 100 parts by weight of the synthetic detergent. Also, it

Fatented Nov. 4, 1958 ice is preferred to have the water-insoluble wax comprised of about 30 to 50% by weight of the final product.

A wide variety of water-insoluble waxes can be used in practicing the present invention, such as carnauba wax, candellila wax, beeswax, petroleum wax, glycol stearate waxes, etc. These waxes may be used singly or in various combinations, and mixtures of water-insoluble mineral, animal and vegetable waxes are useful. Similarly, various normally-solid synthetic detergents may be used. The combination. of petroleum wax with an alkyl aryl sulfonate detergent has been found to give particularly good results, and is therefore preferred.

Other ingredients can also be incorporated in the mixture, in small proportions. Lanolin may be used as a skin conditioning agent. Germicidal compounds like bithionol and other chemicals may be used for other purposes.

After the ingredients have been formed into a uniform molten mixture within kettle 10, the mixture is flowed into a rectangular mold or tray 13, which is preferably supported on an agitating table 14. The movement of the tray on table 14 is continued until the material has settied into a uniform cake. It can then be further hardened by standing at a racking station (not shown). When hardened sufficiently for the initial cutting operation it is passed to a cutting table 15. In this connection, it should be noted that tray 13, prior to the introduction of the molten mixture therein, is provided with a liner for the bottom thereof, the liner consisting of a plurality of flexible pallets 16a, 16b, and 160. These pellets are arranged side by side to completely cover the bottom of the molding tray 13, as illustrated in the drawing.

At the cutting station on table 15 a knife blade 17 is used to divide the cooled and partially hardened material into sections, the cuts being made above the junction lines between the flexible pallets. For example, the first line of severance is indicated at 18, which is aligned with the juncture line of pallets 16b and 16c. Mold tray 13 is also provided with collapsible sides, which may be hinged as indicated in the drawing. This permits the sides of the tray to be opened after the completion of the cutting operation just described. Then the sections of solidified material are removed on their respective pallets, as indicated by the sections 1%, 19b and 190 supported respec tively on pallets 16a, 16b and 160.

These pallet-supported sections are then cut partway through along intersecting lines to form a plurality of cakes joined at their bottoms adjacent the pallets. For example, this can be done by first passing the palletsupported sections through a scoring machine designated generally at 20. As shown, the results of the initial scoring operation are the formation of a series of parallel grooves extending in one direction across the sections and part of the way through the sections. These sections are then turned sideways as indicated at 21, and then passed through a second scoring machine designated generally by the number 22. The second scoring operation forms another series of parallel spaced grooves across the top of the material and preferably at right angles to the first set of grooves. It is also preferred to have this second set of grooves extend only part of the way through the material.

After the completion of the scoring operations the sections, while still attached to the flexible pallets, are passed to a cooling station at 23 where the wax-detergent mixture is further cooled and hardened. After the material reaches substantially room temperature, the sections are removed to a further processing station at 24 where the pallets are separated from the scored sections. This is done by inverting the sections and peeling or stripping off the flexible pallets, as indicated in the drawing. A rolling-stripping action involving the flexing of the pallets has been found to be the only satisfactory means for removing the" pallets without breaking or marring the detergent material. Thereafter all that remains to be done is to further divide the sections along the partial lines of severange thereacross, which can readily be ac'-- complished by simply breaking off any desired number of cakes. The divided cakes are then packaged in any suitable manner.

' Example Following the method just described and using equipment similar to that shown diagrammatically in the drawing, a. commercial product was prepared in accordance with this invention; The formulation of this product was as follows:.

In the above formulation, the synthetic detergent was Ultrawet K, which is an alkyl benzene sodium sulfonate detergent manufactured by the Atlantic Refining Company. Thewater-insoluble wax consisted of a mixture of such waxes, namely 34 parts by weight of petroleum, 1 part candellila, 1 part castor, and 1 part spermacetti. Thefatty acid was lauric acid, but other fatty acids such as myrstic. or palmitic acid could be substituted. The bacteriostat was bithionol. There was also incorporated in the material less than 1 part each of oil-soluble chlorophyll and aperfume ingredient.

In forming the mixture of the above ingredients, the wax, lanolin, and fatty acid were melted together at approximately 200 F. The detergent powder was then added to the hot mixture and stirred until the mixture reached a creamy consistency. Then the other ingredients were added and the stirring was continued until all ingredients were uniformly dispersed in the mixture.

The hot mix was then poured into specially constructed trays like those previously described. More specifically, the trays employed consisted of a rigid board 43 x 19" with'hinged walls extending thereabove for about 1 /2. Three sections of rubber (neoprene) were used as the pallets to cover the bottom of the tray, thesections having dimensions of about 16 x 19".

The trays were then agitated until the contents levelled otf to a smooth upper surface, thereby forming a large cake 46 x 17 x /s thick. This cake was allowed to cool at about 100 F., and was then divided into three section by cutting it through from side to side of the trays, where theseCtiOnS of rubber butted together. Each of the sections of the cake with the rubber pallets still attached was then put through two scoring machines makingscores /2" deep; and thereby producing sections 1%" long x wide x thick, these small sections being joined together at their bottoms by material A; thick.

The scored sections were then cooled for several hours, after which the rubber pallets were removed by a stripping process, as already described. The scored sections were then divided into smaller sections for packaging.

It will be understood that the-process described above is susceptible to many variations without departing from the basic concepts of this invention. For example, the specific ingredients employed can be varied considerably, providing a water-insoluble wax and a solid synthetic detergent are used as the principal ingredients. Also, it is of importance that no pressure should be used in the process, so'that the resulting cakes are uncompressed, the detergent material beingbound into a compact mass solely by the binding action of the water-insoluble wax.

I claim:

1. The method of producing synthetic detergent cakes, comprising forming a molten mixture from a water-insoluble wax and a normally-solid synthetic detergent, flowing said mixture into a mold having collapsible sides and a plurality of flexible pallets in the bottom thereof, cooling and solidifying said mixture within said mold, then collapsing the sides of said mold, cutting the molded body into separate sections along the junction lines betweensaid flexible pallets, separating said sections on said pallets, cutting said sections part of the way through along intersecting lines to form a plurality of cakes joined at their bottoms adjacent said pallets, next separating said pallets from said sections by a rolling-stripping actioninvolving the flexing of said pallets, and thereafter further dividing said sections along the partial lines of severance thereacross preparatory to packaging said cakes.

2. The method steps of claim 1 in which said mixture contains from 50 to parts by weight of said wax to 100 parts of said detergent.

3. The'method steps of claim 1 in which said synthetic detergent is a member of the class of alkyl aryl sulfonate synthetic detergents and in which said waterinsoluble-wax consists principally of mineral wax.

4. In a method of producing synthetic detergent cakes, the steps comprising forming a fluid mixture composed principally of a water-insoluble wax and a normally-solid synthetic detergent, flowing said mixture into a mold having collapsible sides and a plurality of flexible pallets in the bottom thereof, solidifying said mixture within said mold, then collapsing the sides of said mold, cutting the molded body into separate sections along the junction lines between said flexible pallets, separating said sections on paid pallets, and thereafter inverting said solidified sections with said pallets attached thereto and stripping said pallets free from said solidified sections.

5. The method steps of claim 4 in which said mixture contains from 50 to 100 parts by weight of said wax per 100 parts of said detergent.

6. The method steps of claim 5 in which said synthetic detergent is a member of the class of alkyl aryl sulfonate synthetic detergents and in which said waterinsoluble wax consists principally of mineral wax.

References Cited in the file of this patent UNITED STATES PATENTS 2,026,214- Chilton Dec. 31, 1935 2,404,671 Vinal July 23, 1946 2,619,680 Marshall Dec. 2, 1952 2,653,913 Van Dijck Sept. 29, 1953 2,734,870 Lewis Feb. 14, 1956 

